Multiple rectifier stack assembly



April 6, 1965 a. BERNsTElN 3,177,406

MULTIPLE RECTIFIER STACK ASSEMBLY Filed June 18, 1962 United States Patent O 3,177,466 MULTIPLE RECT 1ER STACK ASSEMBLY Bernard Bernstein, Brooklyn,rN.Y., msignor tto General Instrument Corporation, Newark, NJ., a corporation of New liersey Filed June 18, 1962, Ser. No. 203,367 9 Claims. (Cl. 317-101) This invention relates to rectiiiers, and more particularly to multiple rectifier stacks housed compactly in a iiat casing.

A known rectier assembly which is widely used in apparatus such as computers comprises a plurality of, usually four, iiat stacks of plates coated with a semiconductor, usually selenium. The stacks are housed in a flat rectangular casing arranged for either wire connection or plug-in mounting, there being a connector at one end of the casing. The provision of four stacks adapts the device for use as a full wave bridge rectifier, but the four stacks may be wired in other ways, the Wiring being external of the casing.

The general object of the invention is to improve rectiier assemblies of the specied character. As heretofore made, each selenium stack included a dummy plate for end Contact, an insulation lining, and a steel clip pressed around the stack. Pigtail connections had to be soldered between the end plates of the stack, and the contacts of the connector at the end of the casing.

Further objects ofthe present invention are to simplify the construction, and to provide a more rugged structure which may be made at less cost, and which eliminates the need for pigtail wiring and soldering operations. Other objects are to eliminate the steel clips, the insulation inside the clips, and the dummy plates. Another object is to apply printed circuitry techniques to the rectier assembly.

To accomplish the foregoing objects, and other more specific objects which will hereinafter appear, my invention resides in the rectier assembly and the elements thereof, and their relation one to another, as are hereinafter more particularly described in the following speciiication. The specification is accompanied by drawings in which:

FIG. l is a perspective view showing a rectifier assembly housing;

FIG. 2 is a section taken approximately in the plane of the line 2 2 of FIG. l, with three of the four stacks omitted;

FiG. 3 is a section taken approximately in the plane of the line 3 3 of FIG. l, with one of the stacks omitted;

FIG. 4 is an elevation showing one face of a printed circuit board used in the assembly, separated from the edge board connector which receives the same;

FIG. 5 shows the opposite face of the printed circuit board; and

FIGS. 6 and 7 illustrate a metal clip which holds a rectifier stack on the printed board and which makes contact with one side of the stack. Y

Referring to the drawing, and more particularly to FIG. l, the housing of the rectifier assembly comprises an Vinsulation block or body 12 which acts as the base of a detachable connector. In the present case the connector has female contacts indicated at 14, that is, the parts 14 are hollow split cylinders. The housing further comprises a hollow rectangular case or shell 16 which is closed on all sides except the ltop as viewed in FIG. l. The insulation block 12 acts as a closure for the open top of the case. l

Referring now to FIGS. 4 and 5 of the drawing, the assembly comprises a printed insulation board 21B having a plurality of metallized-areas 22, 24, 26 and 28 for receiving dat rectier cells. One or more cells, in this case three cells, are stacked on each such area, as is indicated at 30 in FIGS. 2 and 3. There are printed circuit lines extending from the areas, these being indicated at 32 and 34 in FIG. 4, and at 36 and 38 in FIG. 5. There is also a metal clip for each stack, such a clip being shown at 4u in FiGS. 2 and 3. An individual clip is drawn separately in FIGS. v6 and 7, and it comprises a full area face 42 for engaging the outer side of the stack, and it further comprises lingers .44 adapted to pass through mating holes inthe printed board.

The other face of the board has a printed line for engaging a linger of each of two clips. In FIG. 4 the printed conductor 46 engages a finger passing through a square hole 4% from the opposite side, and the printed conductor 50 engages a finger passing through square hole 52 from the opposite side. In FIG. 5 the printed line 54 engages a finger passing through square hole 56 from the opposite side, and printed line 58 similarly engages a finger passing through square hole 60.

in all, there are twice as many printed conductors as there are stacks, there being one printed conductor connected to each side of each stack.

In the preferred and typical case the cells are selenium cells. The cells are substantially square. The printed board 20 is rectangular in outline. The four areas 22, 24, 26 and 28 are all disposed on the longer axis of the printed board, but the areas 22 and 24 on one side are offset or longitudinally displaced relative to the areas 26 and 28 on the opposite side. The` square holes for the fingers of the retainer clips are similarly offset, so that the iingers of the clips on one side remain clear of the ngers of the clips on the other side. They are also clear of the printed areas because they spring outward in the square hole.

All of the printed lines terminate at the edge 60 of the printed board. Such a termination adapts the same for reception by an edge board connector. In the present case this has spring contacts 62 (FIG. 4) which engage the printed lines, The contacts 62 may be any one of a numaber of known and relatively standard types heretofore developed for use with detachable printed circuit boards. In the present case the contacts 14 along one side of the connector base 12 have leaf spring strips 64 (FIG. 2) which are reversely bent to form the Working part 66, and the contacts 68 at the other side of the base 12 have spring strips '70 which are reversely bent to form the Working part 72. The spring pressure at 66 and 72 is well maintained by the confinement of the parts 64 and 70 between the insulation side walls of the case 16.

It will be understood that the contacts 14 are insulated from the contacts 63. In the present case there are eight spring contacts, four on each side for engaging the four printed lines on each side. The ends of these lines are properly located to register with the spring contacts of the connector.

In FIGS. l and 4 there are twice as many female elements 14 as there are spring contacts, but this is precautionary in that in the present construction each spring contact happens to have two socket portions 14 embedded in the insulation base 12. This has the advantage of better' supporting and assuring proper orientation of the spring contact.

In they particular case here shown the selenium cells are rated at 25 volts, and three cells are used in series in each stack, for a rating of volts. Each cell is about 1/2 inch square in area. Because there are four stacks, the device -rnay be used as a full wave bridge rectifier, but it also may be used as a center contact rectifier, and in various other ways, because the Wiring is external and therefore depends on the connections made to and between the contact elements 14 and 68.

applied to the `apparatus receiving the same, when is approximately 21/2 inches by 11/2 Vinches by 1A inch. f

The unit may be detachably plugged into larger apparatus, typically a computer, or individual wires wi-th pin ends kmay be pushed into the contacts 14 and 68.

It will be understood that the quantitative values and dimensions are given solely by way of example, and are not intended to be in limitation of the invention.

The manufacture ofthe rectifier assembly is relatively simple and inexpensive.V The insulation boards 2t) may be circuit board material such as epoxy glass board having a thickness of 1/32 inch. It is printed with copper in accordance with known printed circuit board techniques, and the copper may be tinned. The copper has an adequate thickness of say 2 mils.

kThe rectifier elementsare simple liat elements utilizing a selenium coating on a metal sheet, typically aluminum. As usual, an alloy or counter electrode is sprayed over the selenium. The clips 4d may be made by conventional methods in a suitable progressive die. The material should be resilient, and may, be Ibrass or berrylium copper, or copper coated spring steel. The area of the body portion of the clip is commensurate with that of the selenium cells.

The fingers 44 are so dimensioned that they are received in the holes in the printed yboard with a snap iit, and exert a contact pressure on the stack. To assemble the parts it is merely necessary to place `a stack of three cells in proper position on the board, and to then apply a clip thereover, this being done -for each stack.

If desired, the board then may be dipped in -a suitable insulation material to protectively coat the same and to help iix the parts in posi-tion.. This is not `a potting operation, but merely a quick dip in a low viscosity material. It may be an epoxy material, but a vinyl material has been found satisfactory.. The coating is carried just high enough to cover the four stacks, but not to cover the upper edge area of the board where it is to engage the' spring contacts of the edge board connector. Y

The finished board is inserted in an edge board connector, and the case 16 is then added. The upper edge of the case may be Ycemented to the insulation 12 of the connector by use of a suitable solvent or cement. The connector is preferably recessed to receive the edge of the case.

The printing on the circuit board is polarized at its upper edge so that the board cannot be improperly related to the edge board connector. The female elements 14 and 68 of the edge board connector are similarly oliset or polarized so that the entire unit cannot be improperly used as a detachable unit.

It is believed that the construction and method of assembly, as well as the advantages of my improved multiple rectifier, will be apparent from the foregoing detailed description. Compared to the nearest similar construction known to me, the new unit eliminates pigtail wires and insulation sleeves for the same, as well as the need for soldering the wires. It eliminates the U-shaped steel clamps previously used to hold the stacks. together, and it similarly eliminates the insulation previously used between the clamps andthe stacks, as well as the dummy metal end plates previously required for pigtail connection. The printed wiring itself acts'as one end plate, andthe spring clip 40 acts as the other end plate. Y n

` It will be understood that while I have shown and ydescribed the invention in a preferred form, changes may be made without departing from the scope of the invention, as sought to be deiined in the following claims.

I claim:

. 1. A. multiple rectifier stack assembly comprising a printed insulation board having a plurality of metallized metal clip for each stack, said clip engaging and electri cally contacting the opposite side of the stack and having tingers passing through holes in the board, the opposite iace of the board having aprinted line for engaging a iinger of each clip, thereby providing printed lines connected to both sides of Yearch stack.

2. A multiple rectilier stack assembly comprising a printed insulation board having a plurality of metallized areas for each receiving and electrically contacting a flat rectifier cell, Aone or more flat cells stacked on each such area, printed circuit lines extending from said areas to an edge of the board, a metal clip for each stack, said clip engaging and electrically contacting ythe opposite side of the stack and having fingers 'passing through holes in the board, the opposite face of the board having a printed linefor engaging a finger of eachl clip and extending to an edge of the board, thereby providing printed lines connected to both sides of each stack, and an edge board connector having resilient contacts so spaced as to engage the ends of the printed lines on Vthe printed board.

3. A multiple rectifier stack assembly comprising a printed insulation board having a plurality of metallized areas each commensurate in size with atiat selenium rectitier cell, one or more selenium cells stacked on each such area, said area serving to electrically Contact the adjacent cell surface, printed circuit lines Vextending from said areas to an edge of the board, a metal clip Vfor holding each stack, said clip engaging and electrically contacting the opposite side of the stack and having fingers passing through holes in the board, the opposite face of the board having a printed line for engaging a linger of each clip and extending to an edge of the board, thereby providing printed lines connected to both sides of each stack, an edge 'board connector having resilient contacts so spaced as to engage the Yends of the printed lines on the printed board, the opposite side of the connector itself having detachable connections of the pin-and-socket type,

y and a ilat rectangular insulation case received around the areas for each receiving and electrically contacting a fiat board and cells and connector contacts. I

4. A multiple rectifier assembly as deiined in' claim 1, in which there are printed areas on both sides of the board'for receiving and electrically contacting rectifier stacks on both sides of the board, and in which the areas on one side are'so displaced relative to the areas on the other side that the lingers of the clips on one side clear the printed areas and the fingers of the clips ofthe other y side, and in which there are printed circuit lines on both sides of the board.

5. A multiple rectifier assembly as defined in claimV 2, in which there are printed areas on both sides of the o board, and in which the edge board connector has spring contacts engaging the lines on one side of the board independently of its spring contact engagementk with theV lines on the other side of the board.' 4

6. A multiple rectierassembly as defined in claim 3, in which there are printedareas on both sides of the board lfor receiving and electrically contacting rectiiier stacks on both sides of the board, and in which the areas on one side are so displaced relative to the areas on the other side that the lingers of the clips on` one side clear the printed areas andthe ingers of the clips on.y theother side, and in which there are printed circuit lines on both sides of the board, all terminating at one edge of the board, and in which the edge board connector has spring contacts engaging the lmesvon one sideof the board independently of its spring contact engagement with the Y lines on the other side of the'board.

7. A'multiple rectifier assembly as defined in claim 1, in which there are two printed areas for cells on each side, the cells on one side being displaced relative to the cells on the other side so that the fingers of the two clips on one side miss and therefore do not contact the printed areas and the fingers of the two clips on the other side, each side having four printed circuit lines, two of said lines on each side extending from stack areas and the other two extending from the holes which receive the lingers of the clips on the opposite side.

8. A multiple rectifier assembly as defined in claim 2, in which there are two printed areas for cells on each side, the cells on one side being displaced relative to the cells on the other side so that the fingers of the two clips on one side miss and therefore do not contact the printed areas and the fingers of the two clips on the other side, each side having four printed circuit lines terminating in one edge `of the board, two of said lines on each side extending from stack areas and the other two extending from the holes which receive the fingers of the clips on the opposite side, said edge board connector having `four spring contacts engaging four lines on each side of the board.

9. A multiple rectifier assembly as defined in claim 3, in which there are two printed areas for cells on each side, the cells on one side being displaced relative to the cells on the other side `so that the fingers of the two clips on one side miss and therefore do not contact the printed areas and the fingers of the two clips on the other side, each `side having four printed circuit lines terminating in one edge of the board, two of said lines on each side extending from stack areas and the other two extending `from the holes which receive the fingers of the clips on the opposite side, said edge board connector having four spring contacts engaging four lines .on each `side of the board.

References Cited bythe Examiner UNITED STATES PATENTS 2,613,244 10/52 Del Camp 317--101 2,810,872 10/57 Nord et al. 317-234 2,911,575 11/59 Roberts 317-234 3,082,356 3/63 Lovell-et al 317-101 FOREIGN PATENTS 589,970 12/59 Canada. 1,050,910 2/52 Germany.

LARAMIE E. ASKIN, Primary Examiner. JOHN F. BURNS, Examiner. 

1. A MULTIPLE RECTIFIER STACK ASSEMBLY COMPRISING A PRINTED INSULATION BOARD HAVING A PLURALITY OF METALLIZED AREAS FOR EACH RECEIVING AND ELECTRICALLY CONTACTING A FLAT RECTIFIER CELL, ONE OR MORE FLAT CELLS STACKED ON EACH SUCH AREA, PRINTED CIRCUIT LINES EXTENDING FROM SAID AREAS, A METAL CLIP FOR EACH STACK, SAID CLIP ENGAGING AND ELECTRICALLY CONTACTING THE OPPOSITE SIDE OF THE STACK AND HAVING FINGERS PASSING THROUGH HOLES IN THE BOARD, THE OPPOSITE FACE OF THE BOARD HAVING A PRINTED LIINE FOR ENGAGING A FINGER OF EACH CLIP, THEREBY PROVIDING PRINTED LINES CONNECTED TO BOTH SIDES OF EACH STACK. 